JP2011033677A - Device for measuring amount of downward rotation of eyeball - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for measuring an amount of downward rotation of eyeball by which an amount of downward rotation of eyeball can correctly be obtained according to each wearer. <P>SOLUTION: The device includes: a sight line location detecting means 3 for detecting the location of a front sight line LF corresponding to a distant eye point FP of a wearer and the location of a lower sight line LN corresponding to a near eye point NP; and a calculating means 5 for calculating a distance between the positions of the distant eye point FP and near eye point NP, detected by the sight line location detecting means 3. Since a wearer is in a state of being wearing glasses when an amount Indih of downward rotation of eyeball is measured, regardless of the position of the wearer, the distant eye point FP and near eye point NP can be correctly detected. Thus, the amount Indih of downward rotation of eyeball can be measured correctly and easily at low costs. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an eyeball downward amount measuring apparatus for spectacle lenses.

  In addition to single-focus spectacle lenses, there are progressive-power spectacle lenses. This progressive-power lens is an aspherical lens having a distance portion region having a refractive power (frequency) corresponding to far vision and a near portion region having refractive power corresponding to near vision. The distance portion region is set at an upper position of the lens, the near portion region is set at a lower position of the lens, and includes a progressive zone in which refractive power changes progressively between these two regions. These areas have no borders and can be seen from a distance to a distance with a single lens. The distance area, near area, and progressive zone are adjusted according to each purpose of use (emphasis on perspective, focus on near distance, focus on near future, full time use, part time use, static use, dynamic use, etc.) Must be performed (optical fitting). Among optical fittings, the amount of downward eyeball movement is important for progressive-power lenses. The amount of downward eyeball movement refers to the distance eye point (FP) on the lens when the spectacle wearer is viewing horizontally, and the eye position on the lens in the near eye direction (near eye point ( NP) is the distance to which the eyeball is moved down from the distance eye point to the near eye point.

In designing such a spectacle lens, information from an eye movement measuring device is obtained, and the eye movement path of the individual in the state of wearing glasses is analyzed by software, so that one or more eye points or average There is a conventional example in which a spectacle lens is custom-designed by specifying a region and correcting a standard lens according to an individual's eye based on the information (Patent Document 1). In the conventional example of Patent Document 1, an eye movement measurement device is used to measure an eye point.
In addition, using the head tracking system and values derived from the statistical analysis results of the wearer's motion statistical model, the individual visual motion pattern of the wearer is determined, and frame selection guidance and the most suitable from multiple known lenses There is a conventional example (Patent Document 2) that encourages lens design.

Special table 2008-521027 gazette Special table 2003-523244 gazette

In the conventional example of Patent Document 1, since the eye movement measuring device is used, the entire device becomes expensive. Patents for determining distance eyepoints and near eyepoints are determined not only by the head and eye movements, but also by the posture of the person wearing the glasses (the wearer). Document 1 cannot obtain an accurate measurement value.
In the conventional example of Patent Document 2, since the head tracking system is used as in Patent Document 1, not only the entire apparatus becomes expensive, but also accurate measurement cannot be performed depending on the posture of the wearer. .

  An object of the present invention is to provide a device for measuring the amount of downward eyeball movement that can accurately determine the amount of downward eyeball movement according to the wearer.

  The downward eyeball movement measuring apparatus of the present invention measures the length from a distance eye point to a near eye point of a spectacle lens that is actually worn by the wearer and is attached to a frame having an upper side and a lower side. A line-of-sight position detecting means for detecting a position of the line of sight corresponding to the far eyepoint of the wearer and a position of the line of sight corresponding to the near eyepoint, and detected by the line-of-sight position detecting means. And calculating means for calculating a distance between the position of the far eye point and the position of the near eye point.

In the present invention with this configuration, the near eye point and the far eye point with different eye gaze positions are detected by the gaze position detecting means while wearing glasses, and based on the positions of these eye points. The amount of downward eyeball movement, which is the distance between the position of the distance eye point and the position of the near eye point, is calculated by the calculation means.
Therefore, according to the present invention, the far eyepoint and the near eyepoint are detected regardless of the posture of the wearer, so that the amount of downward eyeball movement can be measured accurately and easily. In addition, since an expensive eye movement measuring apparatus as in the conventional example and expensive software for analyzing the eye movement path from information output by this apparatus are not required, the apparatus can be provided at low cost.

In the present invention, the line-of-sight position detecting means captures a front image including light irradiating means for irradiating a wearer's eyeball with light, and reflected light reflected by the wearer's eyeball with light irradiated by the light irradiating means. It is preferable to have a configuration including a front imaging unit that moves the light imaging unit and the front imaging unit along the periphery of the eyeball.
In the present invention having this configuration, the positions of the distance eye point and the near eye point can be obtained accurately by reflecting the light emitted from the light irradiating means with the eyeball and capturing the image with the front imaging means.

The calculation means includes a forward tilt angle θ of the frame, an angle β formed by a downward line of sight connecting the eyeball center and the near eyepoint, and an eyeball side plane of the spectacle lens, and the eyeball center and the distance eyepoint. An angle γ between the frontal line of sight and the eyeball side plane of the spectacle lens, and an angle δ between the eyeball side plane of the spectacle lens and a normal line taken from the position of the lower end of the side surface of the spectacle lens to the lower line of sight From the distance K between the lower end position and the front line of sight, and the normal distance M from the lower end position to the lower line of sight, from the lower end of the glasses side surface of the frame to the near eye point The length N of the near eye point
N = M / COSδ (1)
δ = 180 ° − (β + 90 °) (2)
β = 180 ° − (α + γ) (3)
γ = 180 ° − (90 ° + θ) (4)
The structure which calculates from the formula of is preferable.
In the present invention having this configuration, the length N of the near eye point can be accurately obtained based on the equations (1) to (4) regardless of the thickness of the spectacle lens.

The front imaging means preferably receives reflected light reflected by the retina of the wearer's eyeball.
In the present invention having this configuration, the reflected light reflected by the retina can be reliably detected as detection light having a wide area through the pupil.

The front imaging means preferably receives reflected light reflected by the cornea of the wearer's eyeball.
In the present invention having this configuration, the reflected light reflected by the cornea has a small area, and therefore, accurate position detection can be performed.

A configuration provided with a forward tilt measuring means for measuring the forward tilt angle of the frame provided with the spectacle lens is preferable.
In the present invention having this configuration, the forward tilt angle can be measured in a state where the wearer wears spectacles, so that an accurate forward tilt angle can be obtained regardless of the wearing state.

1 is a schematic view of a spectacle lens measured by a downward eyeball movement measuring apparatus according to a first embodiment of the present invention. (A) (B) is a schematic block diagram of the downward eyeball amount measuring apparatus concerning 1st Embodiment. (A)-(C) are the schematic of the image which image | photographed the wearer wearing spectacles with the front imaging means. (A)-(C) are the schematic of the image which image | photographed the wearer wearing spectacles with the front imaging means. Schematic of the image imaged by the forward tilt angle measuring means. Schematic for calculating | requiring the length of a distance eyepoint. Schematic for calculating | requiring the length of a near eye point. (A) (B) is a schematic block diagram of the downward eyeball amount measuring apparatus concerning 2nd Embodiment. (A)-(C) are the schematic of the image which image | photographed the wearer wearing spectacles with the front imaging means. (A)-(C) are the schematic of the image which image | photographed the wearer wearing spectacles with the front imaging means.

Embodiments of the present invention will be described below with reference to the drawings.
In the present embodiment, a progressive power lens is used as the spectacle lens. In the present embodiment, the vertical direction when wearing glasses is described as the up and down direction, and the horizontal direction when wearing glasses is described as the left and right direction.
[Glasses lens]
As shown in FIG. 1, the spectacle lens 10 includes a distance portion region 11 located above, a near portion region 12 located below, and the distance portion region 11 and the near portion region 12. It has a progressive zone 13 and a side region 14 adjacent to the side of the progressive zone 13.

The distance portion region 11 has an average power having a relatively low plus power suitable for far vision. In particular, the distance eye point FP is a position through which a horizontal line (that is, a line of sight) passing through the center of the pupil when the wearer performs a front view.
The near portion area 12 has an average power having a relatively high plus power suitable for near vision (for example, reading). In particular, a near eye point NP is a position through which a line of sight passes when the wearer views near (downward).

The progressive zone 13 is a region in which the relative positive average addition power changes progressively between the distance portion region 11 and the near portion region 12. A straight line that passes through the distance eye point FP and extends in the left-right direction is defined as a distance eye point line FL. A straight line that passes through the near eye point NP and extends in the left-right direction is defined as a near eye point line NL. The distance (length) between the distance eye point line FL and the near eye point line NL is the eyeball downward amount Indih, and this eyeball downward amount Indih is the measurement object of this embodiment.
The distance from the boundary line between the distance portion region 11 and the progressive zone 13 to the distance eye point FP is the distance eye point height Fh. The length (distance) between the boundary line between the distance portion region 11 and the progressive zone 13 and the boundary line between the progressive zone 13 and the near zone region 12 is the progressive zone length SPh.
The side area 14 is an area called an astigmatism area. Usually, the wearer does not see an object through the side region 14 because the object looks double when viewed through the side region 14.

The spectacle lens 10 is obtained by molding such a progressive-power lens, and the obtained spectacle lens 10 is attached to the frame 20 to become spectacles.
The frame 20 includes a frame frame 21 that is attached to the spectacle lens 10 and encloses in a frame shape, a bridge 22 that connects the left and right frame frames 21, and a temple 23 that is rotatably attached to the frame frame 21 via a hinge. (See FIG. 5). The frame 21 has an upper side 21U, a lower side 21D, and a side 21S. The distance between the upper side 21U and the lower side 21D is the eyeglass lens height Bh, and the distance from the distance eye point FP to the upper side of the frame is the upper frame height Oh. The distance from the lower side 21D of the frame 21 to the near eye point NP is the lower frame height Uh.

[First Embodiment]
The downward eyeball movement measuring apparatus according to the first embodiment will be described with reference to FIGS.
FIGS. 2A and 2B are schematic configuration diagrams of the downward eyeball movement measuring apparatus according to the first embodiment.
2A and 2B, the downward eyeball movement measuring apparatus 1 measures the forward tilt angle θ of the frame on which the eye gaze position detecting means 3 for detecting the gaze position of the wearer and the spectacle lens 10 is provided. An anteversion angle measuring means 4 and an arithmetic means 5 for calculating an eyeball inversion amount Indih based on outputs from the line-of-sight position detecting means 3 and the anteversion angle measuring means 4 are provided.

The line-of-sight position detection means 3 detects the position of the line of sight corresponding to the far eye point FP of the wearer and the position of the line of sight corresponding to the near eye point NP, and irradiates the eyeball E of the wearer with light. Light irradiating means 31, front image capturing means 32 for capturing a front image including reflected light reflected by the eyeball E of the wearer, and the light irradiating means 31 and the front image capturing. A moving mechanism 33 for moving the means 32. The light irradiation means 31 and the front imaging means 32 are provided in a common casing 30, and the casing 30 is connected to a moving mechanism 33 that rotates about the center of the eyeball E.
The light irradiation means 31 is composed of a near infrared LED.

The front imaging means 32 has a configuration in which reflected light that has been reflected by the retina of the wearer's eyeball E and passed through the pupil is imaged by the camera, and the position of the pupil due to retinal reflection is detected by the image processing unit based on the captured data. is there.
FIG. 2A shows a state in which the position of the distance eyepoint is imaged. In FIG. 2A, when the wearer faces the front and the front line of sight LF passes through the distance eye point FP, the front imaging means 32 detects the position of the pupil.
In order to detect the position of the pupil, the image processing unit assumes that the pupil portion of the image is an ellipse, calculates the ellipse center based on the formation condition of the parallelogram inscribed in the ellipse, and intersects with a straight line passing through the ellipse center. The contour points are removed from the relationship of the contour points, and the ellipse parameters after the removal are obtained from the least square method.

That is, the method for detecting the position of the pupil is as shown in FIG. FIG. 3 is a schematic view of an image 32 </ b> A obtained by capturing the wearer wearing glasses with the front imaging means 32. This image 32A is displayed on the display unit of the calculation means 5 described later.
In FIG. 3, the eyeball E of the wearer is shown together with the eyeglass lens 10 in the image 32A, and an angle display portion 32B is provided on the upper right of the image 32A of the eyeball E. This angle display part 32B is a display part which shows the angle in the vertical plane centering on the eyeball E of the wearer of the front imaging means 32 by [°]. In FIG. 3, since the wearer is facing the front (looking in the horizontal direction), the angle is 0 °.

  As shown in FIG. 3A, first, an image of the wearer is captured by the front imaging unit 32 without using the light irradiation unit 31. In FIG. 3A, the same image as the image captured by a normal camera is shown, so that the pupil portion EC of the eyeball E is imaged black. In this state, when light is emitted from the light irradiation unit 31 toward the eyeball E, the color of the pupil part EC changes in the image captured by the front imaging unit 32 as shown in FIG. Specifically, the color of the pupil part EC changes from black to red as so-called red eyes. Then, as shown in FIG. 3C, the image of FIG. 3A is removed from the image of FIG. 3B, leaving an image of only the pupil portion EC. Then, the position of the pupil part EC is detected according to the method described above.

FIG. 2B is a schematic diagram showing a state in which the position of the near eye point is imaged. In FIG. 2B, when the wearer turns downward and the line of sight passes through the near eye point, the front imaging means 32 detects the position of the pupil.
FIG. 4 is a schematic view of an image 32A obtained by capturing the wearer wearing glasses with the front imaging means 32 when the line of sight of the wearer passes through the near eye point. Since FIG. 4 shows a state in which the wearer faces downward, the wearer's eyes are imaged more flatly than in FIG.
In FIG. 4, the image 32 </ b> A shows the eyeball E of the wearer together with the eyeglass lens 10. An angle display section 32B is provided on the upper right of the image 32A. In FIG. 4, since the wearer's line of sight is directed toward the near eye point (looking obliquely below), the angle is larger than 0 °, and in FIG. 4, 30 ° is displayed.

  As shown in FIG. 4A, first, an image of the wearer is captured by the front imaging unit 32 without using the light irradiation unit 31. In FIG. 4A, the pupil portion EC of the eyeball E is imaged black. In this state, when the light irradiation means 31 emits light toward the eyeball E, the color of the pupil part EC changes (red) in the image picked up by the front image pickup means 32 as shown in FIG. 4B. And imaged. Then, as shown in FIG. 4C, the image of FIG. 4A is removed from the image of FIG. 4B, leaving an image of only the pupil portion EC. Then, the position of the pupil part EC is detected according to the method described above.

In FIG. 2, the moving mechanism 33 includes an arc-shaped dome 33A and a drive unit (not shown) for driving the casing 30 provided with the light irradiation means 31 and the front imaging means 32 along the dome 33A. Prepare. This drive unit has an appropriate configuration such as a motor, a gear mechanism, and a chain.
The forward tilt angle measuring means 4 includes a camera that captures the side surface of the wearer wearing the spectacle lens 10 and an image processing unit that calculates the forward tilt angle θ of the frame 20 based on the image captured by the camera. Is provided.
An image taken by the forward tilt measuring means 4 is shown in FIG. In FIG. 5, a state in which the wearer is oriented in the horizontal direction is captured, but the image processing unit is inclined forward based on images such as the position of the temple 23 of the frame 20 and the position of the frame frame 21 of the wearer. θ is calculated. Data of the forward tilt angle θ calculated by the image processing unit is sent to the calculation means 5. In this embodiment, the image processing unit may be omitted, and an operator may directly obtain the forward tilt angle θ from the screen imaged by the camera, and this value may be separately input to the calculation means 5.

In FIG. 2, the calculation means 5 is a personal computer having an external input unit such as a keyboard, a display unit, and a calculation unit. Information output from the front imaging unit 32 and the forward tilt measurement unit 4 and other information are output from the personal computer. The downward movement amount Indih of the eyeball is calculated based on the information.
The downward eyeball amount Indih is a distance (length) between the distance eye point line FL and the near eye point line NL.
FIG. 6 is a schematic diagram for obtaining the length of the distance eye point, and FIG. 7 is a schematic diagram for obtaining the length of the near eye point.

  As shown in FIGS. 6 and 7, the forward tilt angle θ input from the forward tilt angle measuring means 4, the frontal line of sight LF connecting the eyeball center obtained by the front imaging means 32 and the distance eye point FP, and the eyeball center and near. A lower line of sight LN connecting the eye point NP, an eyeball downturn angle α formed by the angle between the front line of sight LF and the lower line of sight LN, an angle β formed by the lower line of sight LN and the eyeball side plane OL of the eyeglass lens, and the eyeball of the eyeglass lens An angle γ formed by the side plane OL and the front line of sight LF, an angle δ formed by the eyeball side plane OL of the spectacle lens and the normal line VL taken from the position of the lower end 20P to the lower line of sight LN, and the lower end 20P of the side surface of the spectacles of the frame 20 A near eye point from the lower end 20P of the frame 20 to the near eye point NP from the distance K between the position and the front line of sight LF, the distance M of the normal line VL from the position of the lower end 20P on the side of the glasses to the lower line of sight LN Into length N is obtained from the following equations (1) to (4). The distance K is the apparent length between the distance eye point FP and the lower end 20P of the spectacle lens 10, and the distance M is the apparent length between the near eye point NP and the lower end 20P of the spectacle lens 10. is there.

N = M / COSδ (1)
δ = 180 ° − (β + 90 °) (2)
β = 180 ° − (α + γ) (3)
γ = 180 ° − (90 ° + θ) (4)
Further, the length L of the distance eye point from the lower end 20P on the side surface of the eyeglasses of the frame 20 to the distance eye point FP is obtained from the following equation (5).
L = K / COSθ (5)
Furthermore, since the eyeball downward amount Indih is a distance between the distance eye point FP and the near eye point NP, the eyeball downward amount Indih is obtained from the following equation (6).
Indih = L−N (6)

In the present embodiment, the above formula is recorded in the memory of the calculation unit.
The distance K between the position of the lower end 20P on the side surface of the glasses 20 and the front line of sight LF is moved from the position where the front imaging means 32 receives light centered on the front line of sight LF to the position where light is received centered on the lower end 20P. It can be obtained as the movement distance in the case. Similarly, the distance M between the position of the lower end 20P and the lower line of sight LN is a movement distance when the front imaging means 32 moves from the position where light is received centered on the lower line of sight LN to the position where light is received centered on the lower end 20P. Can be sought. Although the movement trajectory of the front imaging means 32 is on an arc, since the movement distance is shorter than the distance between the eyeball and the front imaging means 32, it can be approximated as a parallel movement.

In the first embodiment having the above-described configuration, a method for obtaining the downward eyeball movement amount Indih will be described. First, the wearer puts on the spectacle lens 10 to be inspected, and the forward tilt angle measuring means 4 measures the forward tilt angle θ.
Then, in a natural state, the wearer turns his gaze toward the front to look far away. The front imaging means 32 is positioned so as to face the front of the wearer, and the front of the wearer is imaged while being moved by the moving mechanism 33. The front imaging means 32 is arranged at a position where the wearer is facing the front and seems to coincide with the line of sight of the wearer, and imaging is started. First, as shown in FIG. 3A, an image of the wearer is captured by the front imaging unit 32 without using the light irradiation unit 31, and light is irradiated from the light irradiation unit 31 toward the eyeball E of the wearer. . As shown in FIG. 3B, when the pupil portion of the image captured by the front imaging unit 32 is red, the position is the distance eye point FP, and the angle is the front imaging unit 32. Remembered. If the pupil portion is not red, the front imaging means 32 is moved little by little to determine the position of the distance eye point FP. Thereafter, the front imaging means 32 is slowly moved downward until the position of the lower end 20P of the spectacle lens 10 becomes the front position, the position is obtained, and only between the distance eye point FP and the lower end 20P of the spectacle lens 10. Measure the upper length K.

After that, in a natural state, the wearer turns his gaze downward to look closer. The front imaging means 32 is moved by the moving mechanism 33 to a position estimated to correspond to the line of sight below, and the wearer is imaged. First, as shown in FIG. 4A, an image of the wearer is captured by the front imaging unit 32 without using the light irradiation unit 31, and light is irradiated from the light irradiation unit 31 toward the eyeball E of the wearer. . As shown in FIG. 4B, when the pupil portion of the image captured by the front imaging means 32 is red, the position is the near eye point NP, which is formed by the front line of sight and the lower line of sight. The angle α is the downward rotation angle of the eyeball. If the pupil portion is not red, the front imaging means 32 is moved little by little to determine the position of the near eye point NP. Thereafter, the front imaging means 32 is slowly moved downward until the position of the lower end 20P of the spectacle lens 10 becomes the front position, the position is obtained, and only between the near eye point NP and the lower end 20P of the spectacle lens 10. Measure the upper length M.
The data measured in the above steps is output to the calculation means 5, and the calculation means 5 calculates the downward eyeball movement amount Indih based on the above-described equations (1) to (6).

Therefore, in the first embodiment, the following operational effects can be achieved.
(A) A line-of-sight position detection unit 3 for detecting a position of the front line of sight LF corresponding to the far eye point FP of the wearer and a position of the lower line of sight LN corresponding to the near eye point NP, and the line-of-sight position detection unit 3 The eyeball downward movement measuring device 1 is configured to include the calculation means 5 that calculates the distance between the position of the far eye point FP detected in step 1 and the position of the near eye point NP. Since the wearer wears glasses when measuring the downward eyeball amount Indih, the distance eyepoint FP and the near eyepoint NP can be accurately detected regardless of the posture of the wearer. It is possible to measure the downward movement amount Indih accurately and easily at a low cost.

(B) The line-of-sight position detection unit 3 includes a light irradiation unit 31 that irradiates light to the wearer's eyeball E, and a front surface that includes the reflected light reflected by the wearer's eyeball E. A front imaging unit 32 that captures an image, and a moving mechanism 33 that moves the light irradiation unit 31 and the front imaging unit 32 along the periphery of the eyeball E are provided. Therefore, by irradiating the eyeball E of the wearer with the light irradiation means 31 and detecting the reflected light from the eyeball E, the accurate position of the distance eye point FP and the position of the near eye point NP are obtained. Can do.

(C) The computing means 5 includes a forward tilt angle θ, an angle β formed by the downward line of sight LN and the eyeball side plane OL of the spectacle lens 10, and an angle γ formed by the eyeball side plane OL of the spectacle lens 10 and the front line of sight LF. The angle δ between the eyeball side plane OL of the spectacle lens 10 and the normal line VL taken from the position of the lower end 20P of the spectacle side surface of the frame 20 to the lower line of sight LN, and the normal line taken from the position of the lower end 20P to the lower line of sight LN Based on the distance M of the VL, the length N of the near eye point is calculated from the above-described equations (1) to (4). Therefore, by previously storing the equations (1) to (4) in the memory of the calculation means 5, the length N of the near eye point can be calculated easily and accurately regardless of the thickness of the spectacle lens 10. can do.
(D) The computing means 5 calculates the length L of the distance eye point based on the forward tilt angle θ and the distance K between the position of the lower end 20P of the frame and the front line of sight LF in the expression (5) described above. It was set as the structure calculated from. Therefore, by previously storing the expression (5) in the memory of the calculation means 5, the length L of the distance eyepoint can be calculated easily and accurately regardless of the thickness of the spectacle lens 10. .

(E) Since the forward tilt angle measuring means 4 for measuring the forward tilt angle θ of the frame 20 is provided, the forward tilt angle θ can be measured in a state where the wearer wears spectacles. Therefore, an accurate forward tilt angle θ can be obtained regardless of the wearing state. Can be sought.

(F) The front imaging means 32 is configured to receive the reflected light reflected by the retina of the eyeball E of the wearer and passing through the pupil EC. Since the reflected light reflected by the retina can be detected as detection light of a wide area through the pupil EC, the detection signal is less subject to noise and position detection of the far eye point FP and the near eye point NP is performed. It can be done reliably.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIGS. The second embodiment is different from the first embodiment in the configuration of the front imaging means, and the rest is the same as the configuration of the first embodiment. In the description of the second embodiment, the same components as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted or simplified.
8A and 8B are schematic configuration diagrams of the downward eyeball movement measuring apparatus 2 according to the second embodiment, and are diagrams corresponding to FIG. FIGS. 9A to 9C are schematic diagrams of images obtained by capturing the wearer wearing glasses with the front imaging unit in the second embodiment, and are diagrams corresponding to FIG. 3. FIGS. 10A to 10C are schematic diagrams of images obtained by capturing a wearer wearing glasses with the front imaging unit in the second embodiment, and correspond to FIG.

8A and 8B, the downward eyeball movement measuring apparatus 2 according to the second embodiment includes a gaze position detecting means 3A for detecting the position of the gaze of the wearer, a forward inclination measuring means 4, and these Computation means 5 for computing an eyeball downward movement amount Indih based on outputs from the line-of-sight position detection means 3A and the forward tilt angle measurement means 4 is provided.
The line-of-sight position detecting means 3A detects the position of the line of sight corresponding to the far eye point FP of the wearer and the position of the line of sight corresponding to the near eye point NP. The light irradiation means 31 and the light irradiation Front imaging means 320 that captures a front image including reflected light reflected by the cornea SE of the eyeball E of the wearer, and a moving mechanism that moves the light irradiation means 31 and the front imaging means 320 33.

The front imaging means 320 has a configuration in which reflected light reflected by the cornea SE of the wearer's eyeball E is captured by a camera, and a reflection point on the cornea SE is detected by an image processing unit based on the captured data. The image processing unit performs the same signal processing as the image processing unit of the first embodiment in order to detect a reflection point on the cornea SE.
FIG. 9A shows a state in which the position of the distance eye point is imaged.
As shown in FIG. 9A, first, an image of the wearer is captured by the front imaging unit 320 without using the light irradiation unit 31. In FIG. 9A, the same image as the image captured by a normal camera is shown, so that the cornea SE of the eyeball E is imaged black. In this state, when light is irradiated from the light irradiation unit 31 toward the eyeball E, the reflection point on the cornea SE is reflected in the image captured by the front imaging unit 320 as shown in FIG. The color changes. Then, as shown in FIG. 9C, the image of FIG. 9A is removed from the image of FIG. 9B, leaving an image of only the reflection point of the cornea SE. Then, according to the same method as in the first embodiment, the position of the reflection point of the cornea SE is detected.

FIG. 8B is a schematic diagram illustrating a state in which the position of the near eye point is imaged.
As shown in FIG. 10A, first, an image of the wearer is captured by the front imaging unit 320 without using the light irradiation unit 31. In FIG. 10A, the reflection point of the cornea SE of the eyeball E is imaged black. In this state, when the light irradiation means 31 emits light toward the eyeball E, the color of the reflection point of the cornea SE changes in the image picked up by the front image pickup means 320 as shown in FIG. To be imaged. Then, as shown in FIG. 10C, the image of FIG. 10A is removed from the image of FIG. 10B, leaving an image of only the reflection point of the cornea SE. Then, the position of the reflection point on the cornea SE is detected according to the method described above.
Also in the second embodiment, similarly to the first embodiment, the downward eyeball amount Indih is obtained from the difference between the distance L of the distance eye point FP and the length N of the near eye point NP. The length L of the distance eye point FP and the length N of the near eye point NP are obtained from the above-described equations (1) to (5).

Therefore, in the second embodiment, the same operational effects as the first embodiment (a) to (e) can be obtained, and the following operational effects can be obtained.
(G) The front imaging unit 320 is configured to receive the reflected light reflected by the cornea SE of the eyeball E of the wearer. Since the area of the reflected light reflected by the cornea SE is small, highly accurate position detection can be performed.

Note that the present invention is not limited to the above-described embodiments, and it goes without saying that modifications and improvements within the scope of achieving the objects and effects of the present invention are included in the contents of the present invention. Absent.
For example, in the above-described embodiment, the forward tilt angle measuring means 4 for measuring the forward tilt angle θ of the frame 20 is provided to configure the downward eyeball movement measuring devices 1 and 2, but in the present invention, the wearer wears glasses with a correct posture. If it is applied, the design data for the forward tilt angle θ can be used as it is for measuring the amount of downward movement of the eyeball, and the forward tilt angle measuring means 4 can be omitted.
Further, it is not always necessary to provide the angle display portion 32B in the image 32A.

  INDUSTRIAL APPLICABILITY The present invention can be widely used in eyeglass stores and the like as an apparatus for measuring the amount of downward eyeball movement of a progressive power lens.

    DESCRIPTION OF SYMBOLS 1, 2 ... Eyeball downward amount measuring apparatus 3, 3A ... Eye-gaze position detection means, 4 ... Forward inclination measuring means, 5 ... Calculation means, 10 ... Eyeglass lens, 11 ... Distance part area | region, 12 ... Near part area | region DESCRIPTION OF SYMBOLS 13 ... Progressive zone, 20 ... Frame, 20P ... Lower end, 21 ... Frame frame, 21D ... Lower side part, 21U ... Upper side part, 31 ... Light irradiation means, 32, 320 ... Front imaging means, 33 ... Moving mechanism, 33A ... Dome E: Eyeball, EC: Pupil portion, EP: Distance eye point, Indih: Eyeball downward amount, LF ... Frontal line of sight, LN ... Downward line of sight, NP ... Near eyepoint, SE ... Cornea, α ... Eyeball downside Angle, θ ... forward tilt angle

Claims (6)

An apparatus for measuring the length from a distance eye point to a near eye point of a spectacle lens mounted on a frame having an upper side and a lower side while being actually worn by the wearer,
A line-of-sight position detecting means for detecting a position of the line of sight corresponding to the far eyepoint of the wearer and a position of the line of sight corresponding to the near eyepoint;
An eyeball downward movement amount measuring device comprising: a calculating means for calculating a distance between the position of the distance eye point detected by the line-of-sight position detecting means and the position of the near eye point. In the downward eyeball movement measuring device according to claim 1,
The line-of-sight position detecting means includes
A light irradiation means for irradiating the wearer's eyeball with light;
A front imaging unit that captures a front image including reflected light in which the light irradiated by the light irradiation unit is reflected by the eyeball of the wearer;
An eyeball downward movement measuring device comprising a moving mechanism for moving the light irradiation means and the front imaging means along the periphery of the eyeball. In the downward eyeball movement measuring device according to claim 2,
The calculation means includes a forward tilt angle θ of the frame, an angle β formed by a downward line of sight connecting the eyeball center and the near eyepoint, and an eyeball side plane of the spectacle lens, and the eyeball center and the distance eyepoint. An angle γ between the frontal line of sight and the eyeball side plane of the spectacle lens, and an angle δ between the eyeball side plane of the spectacle lens and a normal line taken from the position of the lower end of the side surface of the spectacle lens to the lower line of sight From the distance K between the lower end position and the front line of sight, and the normal distance M from the lower end position to the lower line of sight, from the lower end of the glasses side surface of the frame to the near eye point The length N of the near eye point
N = M / COSδ (1)
δ = 180 ° − (β + 90 °) (2)
β = 180 ° − (α + γ) (3)
γ = 180 ° − (90 ° + θ) (4)
The apparatus for measuring the amount of downward movement of the eyeball, which is calculated from the formula: In the eyeball downward movement measuring device according to claim 3,
The frontal imaging means receives the reflected light reflected by the retina of the wearer's eyeball. In the downward eyeball movement measuring device according to claim 4,
The frontal imaging means receives the reflected light reflected by the cornea of the eyeball of the wearer, and the downward eyeball movement measuring device. In the downward eyeball movement measuring device according to any one of claims 2 to 5,
An apparatus for measuring the amount of downward movement of the eyeball, comprising forward tilt angle measuring means for measuring the forward tilt angle of the frame provided with the spectacle lens.

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